(CNN) — Turmoil broke out in Salt Lake City after police shot a 17-year-old, with many questioning whether the shooting was necessary.

The ordeal started Saturday night when officers saw two males with metal objects attacking another male outside a homeless shelter, Salt Lake City police said.

Officers told the attackers to drop their weapons. One of them did, police said. The other “continued to advance on the victim and was shot by officers.”

That’s when the turmoil ensued.

A crowd gathered and hurled bottles and rocks at officers, police said. Four people were arrested for crimes related to civil disorder.

Police have not released the name of the 17-year-old because he is a minor. But Selam Mohammed told CNN affiliate KSTU he saw police shoot his friend during an altercation — and gave a different account of what happened.

Mohammed said his friend had picked up a broken broom stick right before police arrived.

“The police said ‘drop it’ once, then they shot him four times,” Mohammed told KSTU.

“We were trying to break it up before the police even came, but the police ran in on foot and pulled their guns out already. They already had them, like, as soon as he was running he was already grabbing for his gun, not even trying to Tase him or anything.”

Police investigation

Both officers involved in the shooting have been placed on administrative leave pending the results of the shooting investigation, the Salt Lake City Police Department said.

The investigation will be led by the Unified Police Department, an agency run by the Salt Lake County sheriff. Afterward, it will go to the district attorney’s office.

The two officers were wearing body cameras at the time, but the “release of the body camera recordings could reasonably be expected to interfere with that investigation,” the Salt Lake Police Department said.

“Because the suspect is currently being screened for criminal charges, release of the body camera recording could create a danger of depriving the suspect of a right to fair trial or impartial hearing.”

Salt Lake City Police Chief Mike Brown described the case as “a tragedy we take very seriously.”

“Our goal is to always de-escalate any type of volatile situation using the minimal amount of force necessary,” Brown said.

Salt Lake City Mayor Jackie Biskupski said she was “deeply saddened and concerned” about the events Saturday night.

“While the shooting is still under investigation, there is no doubt what happened is a tragedy for all involved and for our entire city,” she said in a statement.

“The use of force by law enforcement against the public can tear at the delicate balance of trust between both sides, and must be taken extremely seriously.”

The president of the NAACP’s Salt Lake City chapter, Jeanetta Williams, told KSTU the concerns about the shooting appear to be less about race and more about the level of force used by officers.

“Did they feel like their life was in danger? Did they have to shoot?” she said. “Those are some of the questions that we’re wanting to ask and see why.”

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